Effects of PACAP on morphologically identified myenteric neurons in guinea pig small bowel.

Abstract

Intracellular microelectrodes were used to examine the actions of pituitary adenylate cyclase-activating peptide (PACAP) on morphologically identified myenteric neurons and glial cells of the guinea pig small bowel. PACAP-27 and PACAP-38 evoked excitatory responses in 96% of after hyperpolarizing (AH)/type 2 neurons. The half-maximal concentration for PACAP-27 was 1.5 nM. The responses consisted of membrane depolarization in association with increased input resistance, suppression of hyperpolarizing afterpotentials, and repetitive spike discharge. Forskolin mimicked the action of PACAP in all AH/type 2 neurons. PACAP excited 36% of S/type 1 neurons. Most of the AH/type 2 neurons had Dogiel II morphology, whereas the S/type 1 neurons were uniaxonal with morphology characteristics of Dogiel I or filamentous neurons. No glial cells responded to PACAP. A selective A1 adenosine receptor agonist blocked the excitatory action of PACAP, and this was reversed by a selective A1 antagonist. The results suggest that excitatory PACAP receptors and inhibitory adenosine A1 receptors are linked to adenylate cyclase in AH/type 2 myenteric neurons.

Statistics

0200400'96'98'00'02'04'06'08'10'12'14'16
Citations per Year

650 Citations

Semantic Scholar estimates that this publication has 650 citations based on the available data.

See our FAQ for additional information.

Cite this paper

@article{Christofi1993EffectsOP, title={Effects of PACAP on morphologically identified myenteric neurons in guinea pig small bowel.}, author={Fievos L Christofi and J. D. Wood}, journal={The American journal of physiology}, year={1993}, volume={264 3 Pt 1}, pages={G414-21} }